A flat-plate-shaped device under test such as a semiconductor integrated circuit undergoes an electrical test to determine whether or not it is manufactured in accordance with the specification. The electrical test of this kind is performed by using an electrical connecting apparatus, such as a probe card, an IC socket, a probe block, a probe unit, or the like, having a plurality of probes or contactors to be thrust to respective electrodes of the device under test. The electrical connecting apparatus of this kind is used to electrically connect the electrodes of the device under test to a tester.
As one of the IC probe cards of this kind, there is one in which multiple plate-shaped probes or contactors are mounted on mounting portions of a base plate or board such as a wiring board, a probe board, etc. in a cantilevered manner to supply power to multiple non-cutting integrated circuits in a semiconductor wafer form simultaneously or in several batches, as described in Patent Documents 1 and 2.
[Patent Document 1]                Japanese Patent Appln. Public Disclosure No. 2005-203606        
[Patent Document 2]                Japanese Patent Appln. Public Disclosure No. 2005-201844        
Each of these conventional techniques comprises at least one contactor group in which a plurality of plate-shaped contactors are arranged in a line and attaches each contactor to a mounting portion such as a wire, a connection land, etc. of a board such as a wiring board, a probe board, etc. by conductive adhesive such as solder. Mounting the contactor to the mounting portion is performed per contactor since the arrangement pitch of the contactors is narrow, which makes it difficult to mount a plurality of contactors simultaneously.
Also, to prevent an adjacent contactor that has been mounted from being damaged at the time of mounting a contactor to a mounting portion and to prevent contactors adjacent to one another from electrically interfering with one another in a state where they are incorporated in an IC socket, the mounting positions to the mounting portions are displaced in a direction intersecting with the arrangement direction of the contactors, that is, are arranged in zigzags.
Meanwhile, in recent years, the number of integrated circuits to be integrated in one semiconductor wafer increases, and thus the arrangement pitch of the electrodes is further reduced. Such a trend tends to proceed further in the future.
However, in each of the conventional apparatuses, the contactors in one contactor group are just divided into two sub groups whose mounting positions differ in a direction intersecting with the arrangement direction of the contactors. Thus, when each of the conventional apparatuses is to be applied to an electrical test of an integrated circuit in which the electrodes are arranged in a fine pitch as described above, the adjacent contactors will contact, and indeed the electrical test cannot be performed.